<template>
  <div class="box">
    <header>我是头部</header>
      <ul class="flex_box">
        <li>这是左边</li>
        <li>这是中间</li>
        <li>这是右边</li>
      </ul>
  </div>
</template>

<script>
import HelloWorld from '../HelloWorld.vue'

export default {
  name: 'App',
  components: {
    HelloWorld
  }
}
</script>

<style>
  *{padding: 0;margin: 0;}
  .box{
    width: 800px;
    height: 100%;
    background: royalblue;
    margin: 0 auto;
    text-align: center;
    color: #fff;
  }
  header{
    width: 600px;
    height: 40px;
    background:crimson;
    line-height: 40px;
    margin: 0 auto;
    margin-bottom: 20px;
  }
  .flex_box{
    display: flex;
    justify-content: space-between;
    width: 600px;
    margin: 0 auto;
  }
  .flex_box li{
    width: 120px;
    height: 160px;
    list-style: none;
    background:crimson;
    line-height: 180px;
  }
</style>
